Which specific critical business processes were transitioned to an asynchronous interaction model?

Critical business processes that are often transitioned to an asynchronous interaction model include:

• Processing orders and payments, where it is important not to block the user and to ensure scalability.
• Sending notifications and emails, to avoid delaying the main workflow.
• Integration with external services, where delays and errors can be prolonged.
• Event processing and logging to enhance fault tolerance.

For example, in an e-commerce system, the order creation process itself can be synchronous, while sending confirmations and updating analytics can be asynchronous via message queues (Kafka, RabbitMQ). This allows unloading the main services and increasing system responsiveness.